package Class;

public class MyTest {
    public static void main(String[] args) {
        String str = "qw4re4vsv3r4t66";
        String newStr = str.replaceAll("[0-9]", "");
        System.out.println(newStr);

        StringBuffer sb =new StringBuffer("abcdert");
        //追加
        sb.append("123");
        System.out.println(sb);
        //插入
        sb.insert(2,"456");
        System.out.println(sb);
        //删除
        sb.delete(1,2);
        System.out.println(sb);
        //反转
        sb.reverse();
        System.out.println(sb);
    }
}
